Re: [PATCH 1/5] pci: add a pci_msix_desc_addr helper

From: Alexander Gordeev
Date: Tue Jul 12 2016 - 08:54:52 EST


On Tue, Jul 12, 2016 at 06:20:14PM +0900, Christoph Hellwig wrote:
> To factor out the calculation of the base address for a given MSI-X vector.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> ---
> drivers/pci/msi.c | 17 +++++++++--------
> 1 file changed, 9 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
> index a080f44..0d94fbf 100644
> --- a/drivers/pci/msi.c
> +++ b/drivers/pci/msi.c
> @@ -207,6 +207,12 @@ static void msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag)
> desc->masked = __pci_msi_desc_mask_irq(desc, mask, flag);
> }
>
> +static void __iomem *pci_msix_desc_addr(struct msi_desc *desc)
> +{
> + return desc->mask_base +
> + desc->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE;
> +}
> +
> /*
> * This internal function does not flush PCI writes to the device.
> * All users must ensure that they read from the device before either
> @@ -217,8 +223,6 @@ static void msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag)
> u32 __pci_msix_desc_mask_irq(struct msi_desc *desc, u32 flag)
> {
> u32 mask_bits = desc->masked;
> - unsigned offset = desc->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE +
> - PCI_MSIX_ENTRY_VECTOR_CTRL;
>
> if (pci_msi_ignore_mask)
> return 0;
> @@ -226,7 +230,7 @@ u32 __pci_msix_desc_mask_irq(struct msi_desc *desc, u32 flag)
> mask_bits &= ~PCI_MSIX_ENTRY_CTRL_MASKBIT;
> if (flag)
> mask_bits |= PCI_MSIX_ENTRY_CTRL_MASKBIT;
> - writel(mask_bits, desc->mask_base + offset);
> + writel(mask_bits, pci_msix_desc_addr(desc) + PCI_MSIX_ENTRY_VECTOR_CTRL);
>
> return mask_bits;
> }
> @@ -284,8 +288,7 @@ void __pci_read_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
> BUG_ON(dev->current_state != PCI_D0);
>
> if (entry->msi_attrib.is_msix) {
> - void __iomem *base = entry->mask_base +
> - entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE;
> + void __iomem *base = pci_msix_desc_addr(entry);
>
> msg->address_lo = readl(base + PCI_MSIX_ENTRY_LOWER_ADDR);
> msg->address_hi = readl(base + PCI_MSIX_ENTRY_UPPER_ADDR);
> @@ -315,9 +318,7 @@ void __pci_write_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
> if (dev->current_state != PCI_D0) {
> /* Don't touch the hardware now */
> } else if (entry->msi_attrib.is_msix) {
> - void __iomem *base;
> - base = entry->mask_base +
> - entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE;
> + void __iomem *base = pci_msix_desc_addr(entry);
>
> writel(msg->address_lo, base + PCI_MSIX_ENTRY_LOWER_ADDR);
> writel(msg->address_hi, base + PCI_MSIX_ENTRY_UPPER_ADDR);
> --
> 2.1.4
>
Reviewed-by: Alexander Gordeev <agordeev@xxxxxxxxxx>